Heat-treatment of sulfonated olefin products



United States Patent M 3,506,580 HEATTREATMENT OF SULFONATED OLEFIN PRODUCTS Joseph Rubinfeld, Brooklyn, N.Y., and Willem Bian Gwan Ouw, Jersey City, N.J., assignors to Colgate- Palmolive Company, New York, N.Y., a corporation of Delaware No Drawing. Filed May 10, 1966, Ser. No. 548,826 Int. Cl. Clld 1/12, 1/14; C07c 139/00 U.S. Cl. 252138 12 Claims ABSTRACT OF THE DISCLOSURE Heat treating an aqueous olefin sulfonate reaction product at substantially atmospheric pressure by contact with a heat transfer material (e.g. a hot gas or hot'solid surface) having a temperature of at least about 260 F. to raise the temperature of the reaction product to at least about 230 F. while driving off water vapor to give a product of 1-12% water content. The aqueous olefin sulfonate reaction product is a material made by sulfonating higher alpha-olefins with dilute S0 and neutralizing the sulfonated material to produce a material containing an anionically active neutralized higher olefin sulfonic acid detergent and anionically inactive material insoluble in aqueous ethanol and soluble in pentane. The heat treatment is effective to decrease the content of said anionically inactive insoluble organic material.

This invention relates to the treatment of sulfonation products of mono-olefins.

The sulfonation of long chain alpha-olefins having, for example, about 12 to 20 carbon atoms, followed by hydrolysis and neutralization to produce salts of alkenesulfonic acids and of hydroxyalkanesulfonic acids has been described previously (as in Dutch patent application 6,407,958 opened for inspection Jan. 25, 1965). In these processes the sulfonation reaction is typically carried out by bringing a stream of sulfur trioxide, highly diluted with an inert gas such as air, into contact with the alphaolefine to produce a viscous acidic product which is believed to contain alkene sulfonic acids and sultones (which are cyclic compounds containing an OSO group attached to two carbon atoms, which carbon atoms are connected to each other either directly or through intervening carbon atoms); according to the aforesaid Dutch patent, the product contains about 35% unsatu rated sulfonic acid and 65% sultone. These reactions may be illustrated as follows:

R R R CCH CH=CH SO products such as-- R R R CCH CH=CHSO H R R R CCH=CH-CH SO H sultones:

manna-orr-om-orn where R is an alkyl radical and R and R are alkyl or hydrogen. The sulfonated product is then hydrolyzed and neutralized, as by treatment with strong aqueous alkali; during this procedure hydrolysis of the sultones is effected to produce hydroxyalkanesulfonic acids. The resulting neutralized product has relatively low detergent power. Its detergent power can be improved to some extent by de-oiling to remove the significant amount (e.g. 15- 25% based on the total organic content) of water-in- 3,506,580 Patented Apr. 14, 1970 soluble material, Such de-oiling is an expensive and wasteful process and its use substantially increases the cost of the detergent material and the capital investment which would be required for detergent production.

The yield of detergent may be increased and the free oil content reduced by treatment of the sulfonation product with sulfuric acid prior to neutralization as disclosed in the copending application of Rubinfeld and Ouw entitled Sulfonation and filed on even date herewith (whose disclosure is incorporated herein by reference) now Patent No. 3,428,654, which is a continuation-in-part of application Ser. No. 477,228, filed Aug. 4, 1965.

Other processes for increasing the yield of detergent are described in published Netherlands patent applications, Nos. 6,414,370 and 6,414,371, which processes also produce an aqueous neutralized reaction product containing the olefin sulfonate and free oil.

'It is an object of this invention to improve the properties of the detergent products obtained by the sulfonation of mono-olefins.

Other objects of this invention will be apparent from the following detailed description and claims. In this description and claims, all proportions are by weight unless otherwise indicated.

In accordance with one aspect of this invention, the free oil-containing aqueous neutralized product of the sulfonation of the olefin is given a heat treatment by contact with a heat transfer material having a temperature of about 260 F., or above, so that the temperature of the neutralized product is raised to at least about 230 F., the heat treatment being effected, at substantially atmospheric pressure, while driving off water vapor from the product so that the water content of the product after said heat treatment is in the range of about l12%. The Water content of the aqueous mixture containing the neutralized product before the heat treatment is preferably above 20%, e.g. within the range of 30-70%,

It has been found that heat treatment in accordance with this invention has resulted in the production of products of lower free oil content, and even of lighter color depending upon the method of manufacture or pretreatment of the sulfonated olefin. The heat treatment has also altered, in a desirable manner, the nature of the free oil content of neutralized products and imparted superior pH stability to such products.

The heat treatment is particularly suitable when applied to the product produced according to the Rubinfeld and Ouw patent application previously mentioned. Furthermore, when such product has been bleached before heat treatment it is found that on heat treatment the bleached color is substantially retained. The heat-treatment has yielded free-flowing, non-tacky products, non-bleeding in a cardboard container, in contrast to the tackiness and tendency to bleed of many sulfonated materials.

The following examples are given to illustrate this invention further.

EXAMPLE 1 An olefin cut having an average molecular weight of about 224, which consisted essentially of olefins having a chain length' of 12 to 22 carbons, and containing about 92% of l-olefins and 4% of trans olefins, was given a twostage treatment. In the first stage it was reacted with gas using an sA zolefin molar ratio of 0.9:1, in a filmtype sulfonation reaction, the olefin being distributed as a falling film over the inner wall of a vertical reaction tube (20 feet high) at the top thereof While an SO -air mixture (containing 4% 80;, by volume) was injected downward at a high volumetric rate into the center of the reaction tube at the top thereof, the reaction temperature being controlled at about F. by the circulation of 85 F. cooling water in the cooling jacket of the reaction tube. From the base of the tubular reactor there was discharged continuously a thick viscous liquid stream of the first stage sulfonation product (or Stage I mix). Entrained air and other gases were removed by a suitable separator. The liquid Stage I mix leaving the tubular reactor and separator was directly injected continously into a recycle loop together with 20% oleum (using 0.15 part by weight of the 20% oleum per part of liquid Stage I mix), these two liquids being added continuously at a pump at the inlet of the recycle loop. The recycling mixture in the loop was maintained at a temperature of about 8595 F. The average residence time in the recycle loop was about 2-5 minutes, the pressure therein was on the order of 5 p.s.i.g., and the material continuously leaving the recycle loop was neutralized directly (in another recycle loop, at 200 F. and 70 p.s.i.g.) with continuously supplied aqueous 25% sodium hydroxide to a pH of 9-10. The average residence time in the second loop was on the order of about 35 minutes.

The neutralized syrupy product was clear, pale yellow and free of solid, undissolved particles and its pH did not change on aging. Analysis indicated that it contained (on a dry basis) 84.0% anionic active detergent, and 2.6% free oil (i.e. material extracted with pentane or petroleum ether from a solution of material in aqueous ethanol). Its inorganic salt content on a dry basis was 13.4%. The water content of this syrup was 55%.

The syrup was blended with additional water, and then there were added successively, in a high speed crutcher, sodium sulfate (supplied as a dry anhydrous finely divided solid) and sodium silicate (supplied as an aqueous 43 /2% solution whose Na O:SiO weight ratio was 122.35), and then sodium tripolyphosphate (supplied as a dry anhydrous finely divided solid), care being taken to have the temperature of the mixture at least 175 F. during and after the addition of the anhydrous polyphosphate, the proportions being such that the resulting mixture contained (on a dry basis) 10% of anionic active detergent, 35% sodium tripolyphosphate (calculated as the anhydrous salt), 40% sodium sulfate (calculated as the anhydrous salt) and 7.5% sodium silicate, the water content of the mixture being about 42%. The foam on the hot mixture collapsed rapidly after the phosphate was added. The resulting mixture had a very low viscosity and was easily mixable and pumpable despite its 5556% solids content. It was pumped at the rate of about 3000 pounds per hour to a spray nozzle at the top of a cylindrical tower 50 feet high, and 8 feet in diameter. Air at a temperature of about 600 F. was supplied at the bottom of the tower at a rate of about 4000 cubic feet per minute and flowed upward turbulently (together with cooler air sucked up from an opening at the base of the tower) countercurrent to the downward flow of the sprayed product. The temperature of the air measured at a point just above the base of the tower was 490 F. and the temperature of the air leaving the top of the tower was about 175 F. The product leaving the base of the tower had a water content of about 8.5%. Its free oil content (based on total organic content) was about 1.3%. The apparent specific gravity of the mass of recovered dry granules was 0.35 gram per cc.

The product exhibits desirable physical properties in solid form and gave excellent performance (in concentrations of 0.05, 0.10 and 0.15%) in the machine washing of cotton clothes (at 120 F.) and showed a desirable low level of foaming.

EXAMPLE 2 An alkene sulfonate was produced, as in Example 1, by two-stage treatment followed by neutralization, using a crude ClS-CZO olefin feedstock, having a boiling range of about 275-315 C. (8% residue), made by cracking paraflin wax, and having the following composition, as reported by the supplier:

Percent Acyclic monoolefins 84 Diolefins and naphthenic olefins 9 Parafiins and naphthenes 5 Cyclic diolefins and dicyclic olefins 1 Aromatics 1 9 2% of the acyclic monoolefins were alpha-monoolefins. The average molecular weight of the monoolefin portion was about 240 and the distribution of olefins was 2% C14, 18% C15, 20% C16, 21% C17, 18% C18, 16% C19, 5% C20.

The neutralizer product was free flowing and had the following analysis: solids content 42.7%; anionic active ingredient 28%; water content 57.3%; free oil (based on the content of anionic active ingredient) 11.7%. The yield of anionic active ingredient based on the monoolefin content of the feed was 98%. The free oil consisted principally of parafiins. The aqueous neutralized product was brown-yellow and had a color value of 700 Klett (measured after dilution with water to give a mixture having a 5% content of anionically active material).

The neutralized product was then blended with a nonionic detergent, builder salts, and sodium linear tridecylbenzene sulfonate and heat treated in the spray tower of Example 1. More particularly, 193 pounds of Water were blended in a crutcher (having an agitator operated at high speed, 200 r.p.m.) with 19 pounds of the alkylbenzenesulfonate (added as an aqueous slurry containing 52.5% solids of which was alkylbenzene sulfonate) and the following ingredients were added successively, each being thoroughly mixed in before the next addition: 22 pounds of Tergitol 45'S9 (an ethylene oxide adduct of one mole of C14C15 alkanol and 9 moles of ethylene oxide); 75 pounds of the syrupy neutralized product described above; 2% pounds of carboxymethyl cellulose; 13 ounces of polyvinyl alcohol; minor proportions of brightening agents and of an antioxidant (2,6-di-tert-butylphenol); 4% pounds borax; 67 /2 pounds of an aqueous 45% solution of sodium silicate (having an Na O:SiO' weight ratio of 122.35); 131 pounds of pentasodium tripolyphosphate (anhydrous). The final mixture had a water content of 45% (determined by azeotropic distillation with xylol) and a solids content, correspondingly, of about 55%. The temperature of the ingredients during the mixing was about 160 F.

The mixture (which was a pumpable slurry) was sprayed under pressure in a manner similar to that described in Example 1. The product taken from the base of the tower was granular and free flowing. Its fiowability was 80%; when all the olefin sulfonate was replaced by an equal weight of the tridecylbenzene sulfonate, the flowability of the granular product, having the same moisture content (8.5%) was only 43%. The fiowability measurements were made in conventional manner, by measuring the time for a given volume of the material to flow through an orifice at the bottom of a standard container, and comparing the flow time with that of a standard dry sand, the latter being considered, for the purposes of the comparison, to have flowability.

The content of free oil in the heat-treated product was only 6%, based on the amount of anionically active ingredient derived from the olefin sulfonate, as compared to the original free oil content of 11.7% on the same basis.

The linear tridecyl benzene sulfonate used in the foregoing example had an average of 13 carbon atoms in its alkyl substituent (about 15 mole percent C-12, 55 mole percent C-13 and 30 mole percent C-14); the alkyl substituent contained about 25 of alkyl groups whose benzene attachment is on the 2-carbon of the alkyl group, the remainder of its alkyl groups having the benzene attachment on the 3-, or higher, carbon atom (e.g. 45 on the 5- or 6-carbon atom).

When all the olefin sulfonate was replaced by an equal weight of the tridecylbenzene sulfonate, the mixture had a tendency to gel in the crutcher. No such gelation or thickening of the composition took place when the olefin sulfonate was present.

EXAMPLE 3 Example 2 was repeated, using a different detergent formulation. More particularly, 142 pounds of water were blended in the crutcher with 49 pounds of the alkylbenzene-sulfonate slurry described in Example 2, and the following ingredients were added successively, each being thoroughly-mixed in before the next addition: 114 pounds of the syrupy olefine sulfonate product of Example 2; 53 pounds of the aqueous 43 /2% solution of sodium silicate described in Example 1; 141 pounds of sodium sulfate (anhydrous); 3% pounds of carboxymethylcellulose; lb. of polyvinyl alcohol; minor amounts of the brighteners and antioxidant used in Example 2; 17 lbs. 3 ounces of soap chips (sodium soap made from 75% tallow fatty acids and 25% coconut oil fatty acids and having a moisture content of 12%); 161 lbs. of pentasodium tripolyphosphate (anhydrous); minor proportions of blue dye. The final mixture contained about 43% water.

The mixture (which was a very thin pumpable slurry) was sprayed as in Example 2. The resulting dry product taken from the base of the tower was granular and free flowing. The moisture content of the granules was 8.5%. The free oil content in the heat-treated product was only about 5%, based on the amount of anionically active ingredient derived from the olefin sulfonate.

In clothes-washing tests, this heat-treated formulation (containing the active ingredients of the detergents in the proportions of about 7% sulfonated olefin, 5% alkylbenzene sulfonate and 3% soap) performed better than a similar formulation containing 12% of the alkylbenzene sulfonate and 3% soap. A large majority of those using the formulations in these tests, which involved five wearings and washings, reported a definite preference for the formulation containing the sulfonated olefin and indicated that many items, such as terrycloth towels, felt softer to the touch. Superior grease removal and superior cleaning of synthetic fibers were also observed. Excellent results in terms of detergency were also obtained when the soap was omitted, using a formulation in which the active ingredients were in the proportion of 10% sulfonated olefin and 5% alkylbenzene-sulfonate. In each case only a relatively small amount of foam was produced during the washing process; this is desirable for many types of automatic washing machines.

Although the color of the neutralized sulfonated olefin was relatively dark (having a Klett value of 900, measured after dilution with water to reduce the concentration of anionically active ingredient to 5%) the sprayed heattreated blue-dyed product of this example was substantially as light in color as a sprayed product made from the 12-3 alkylbenzene sulfonate-soap formulation mentioned above, even though the Klett value of the alkylbenzenesulfonate was only 50.

EXAMPLE 4 An olefin sulfonate syrup was prepared, using the same general method as in Example 1 from an olefin of the following analysis (according to its supplier): total olefins 98%, straight chain alpha olefins 89%, branched and naphthenic olefins 7%, diolefins 2%, parafiins 2%, the average molecular weight being 228 and the carbon number distribution being 1% C14, 27% C15, 29% C 16, 28% C-17, 14% C-18, 1% C-19.

The syrupy product containing 34% solids, but no undissolved particles, 29.4% anionic active ingredient, and 2.09% free oil (on a dry basis: 86.5% active ingredient, 5.9% free oil, and the balance, salt) was dropped continuously onto the nip between two contacting parallel horizontal cylindrical steel rotating drums, each internally heated, by steam underpressure, to 300350 F.; the drums rotated slowly in opposite directions with their upper surfaces moving away from the nip and the material being dried thereon was scraped away continuously by stationary scraper blades contacting the drum surfaces at about 180 of rotation from the nip. The average tem perature of the mass of material on the rolls was about 250 F. The average residence time before removal of the heat-treated material from the blades was about 5 minutes.

The heat-treated material contained about 96.9% solids (i.e. 3.1% water). On a dry basis, it contained 90.3% of the anionically active ingredient and 2.8% free oil, as compared to the original 5.9% of free oil.

The color of the heat-treated material (on redissolution in water) was appreciably lighter than that of the original untreated neutralized solution (color value 310 Klett vs. 800 Klett).

EXAMPLE 5 A neutralized syrup produced as in Example 2 was heattreated as in Example 4. The proportion of free oil based on the content of anionically active ingredient was only 2.6% as compared to 11.7% in the original product.

EXAMPLE 6 The syrup of Example 4 was mixed with pentasodium tripolyphosphate, sodium silicate and sodium sulfate as in Example 1, and thenheat-treated as in Example 4. The product contained 1.4% free oil based on the amount of anionically active ingredient.

EXAMPLE 7 A Stage I neutralized product was produced from the olefin mixture of Example 4, following the procedure for the production of the Stage I mix described in Example 1 and then hot-neutralizing the Stage I mix with sodium hydroxide in a manner similar to the neutralizing procedure described in Example 1. The resulting solution had a pH of 10 and contained 47% water and 53% solids (by difference); the content of free oil in the slurry was 9% and the content of alcohol-insoluble material was 2% (the alcohol-insoluble content, measured after ignition of the alcohol-insolubles was 1.6%). Directly after the neutralizing step the slurry was heat-treated as in Example 4.

On redissolution in water, the heat-treated material formed a clear solution which had a pH of 10. The pH remained stable on standing for 2 weeks (after which testing was discontinued with the solution still at pH 10). In contrast, the pH of a sample of the original solution drifted down from pH 10 to pH 1 in less than a day of standing.

The free oil content of the original untreated neutralized solution included paraflins, olefins and sultones. After the heat-treatment, its free oil content was very largely paraflins.

EXAMPLE 8 The neutralized slurry of Example 4 was placed on an aluminum foil surface and was subjected to radiant heat from a red hot source a few inches away. Even after the evaporation of all the water, charring was not noticeable. In contrast, alkylbenzene sulfonates char appreciably on such treatment.

EXAMPLE 9 contained 9% of the anionically active olefin sulfonate,

7 of the lauryl alcohol, 45% of the phosphate, of the silicate, 8% of water and the balance substantially all sulfate; it gave very good detergent performance.

The moisture, or water, contents given in the above examples include water present as a salt hydrate as well as free water.

The content of anionically active material can be determined in known manner by titration wtih cetyl trimethylammonium bromide using an acidified two-phase mixture containing chloroform, water, methylene blue and the material to be tested. The color concentrates almost exclusively in the lower, chloroform, layer. On addition of cetyl trimethylammonium bromide or other long chain cationic reagent and agitation, the color shifts into the upper, aqueous, layer; the endpoint of the titration may be taken as the point at which the lower layer is less blue than the upper layer, and has a green appearance.

The free oil content can be determined by taking up the sample in ethanol (e.g. using 50 ml. of ethanol for each 1 to 3 g. of anionically active ingredient in the sample), and then repeatedly extracting with pentane (petroleum ether); for example, extracting 5 times, using 50 ml. of the extractant for each extraction.

The preferred method of heat-treating is by spraying the aqueous material in a heated condition (e.g. at a temperature in the range of about 100 to 210 F.) into a heated gas, preferably air (e.g. at a temperature of 300- 700 F.) As shown in the above examples, the aqueous material is very fluid, even when relatively concentrated, and can be pumped and sprayed readily, to form dried freely flowing particles having water contents well below 12% and preferably below about Other methods of heat-treating include exposure to hot rolls or to film type scraped wall heaters in which the material being treated passes continuously through the heater, being spread as a thin film on a heated metallic surface, scraped off the surface and respread, preferably while being subjected, as a film, to hot air flowing through the equipment. In these methods the material in contact with the heated heat transfer material is in attenuated form (e.g. in the form of a film, thread or droplets whose thickness or diameter is usually less than about A; inch), a surface of the heated attenuated material being exposed to an evaporative atmosphere. Heat treatment while the water content of the material is maintained at higher levels than those specified above does not give the advantageous results previously described.

For best results, the temperature attained by the material during the heat treatment should not exceed the decomposition temperature of the anionically active alkenyl sulfonate contained therein.

The duration of the heat treatment is preferably brief, generally well below 10 minutes. In the preferred form of the invention, in which the material is sprayed into a current of heated air, the duration of the heat treatment is less than a minute, e.g. about 20 to 50 seconds.

The process of this invention is particularly useful for the treatment of free oil-containing aqueous reaction mixtures, obtained by a process of sulfonating higher alpha-olefins and neutralizing the sulfonated material. The higher alpha-olefin feedstock may contain, for example, alpha-olefins of 8-25 carbon atoms; preferably the number of carbon atoms is in the range about 12-21 carbon atoms. The aqueous reaction mixtures to be treated contain anionically active material comprising alkenyl sulfonates, of the same number of carbon atoms as the feedstock, and usually contain also the corresponding hydroxyalkanesulfonates. The proportion of alkenyl sulfonates is preferably at least about as high as the proportion of hydroxyalkanesulfonates, and still more preferably at least about twice the proportion of hydroxyalkanesulfonates. The free oil may be present in varying proportions, e.g. the ratio of the free oil to the anionically active material in the reaction product prior to the heat treatment may be in the range of about 1:4 to

1:100. The free oil content is usually above about 1% (based on the total organic content, i.e. the content of anionically active material plus free oil) and, as indicated earlier, may be as high as 15-25% when certain processes are employed. The free oil usually contains an appreciable portion of hydrocarbons of about the same number of carbon atoms as the feedstock, including higher alkanes (which are generally present as impurities in the feedstock and which have passed through the sulfonation reaction substantially unaffected) and higher olefins. Usually, higher sultones are present in the free oil in varying amounts; when the sulfonation reaction has been effected simply with diluted S0 the sultone content is relatively high, often over 70% to of the total free oil, but when the sulfuric acid treatment is employed the sultone content is much lower.

The process of this invention is extremely useful in connection with neutralized products made from relatively impure feedstocks containing on the order of 5% or more of higher alkanes, since even the sulfuric acid treatment appears to leave the alkane content unaffected so that the product, before the heat treatment of this invention, has a free oil content higher than is desirable for many purposes; feedstocks of this type are illustrated in Examples 2 and 3.

The alkenyl sulfonates, and any hydroxyalkane sulfonates, are preferably salts of alkali metals, e.g. sodium or potassium, most preferably sodium. It is, however, within the broader scope of the invention to treat neutralized product in which other salts are present in place of, or in addition to, the alkali metal salt, e.g. calcium, magnesium, or mono-, dior triethanol-ammonium salts.

The material being heat-treated may be simply an aqueous solution or dispersion of the neutralized olefin sulfonate or it may comprise additional materials such as other anionic, amphoteric, or nonionic detergents, builder salts, brighteners, germicides, foam boosters, etc.

Examples of other anionic detergents are other sulfonates such as alkylbenzenesulfonates particularly alkali metal (e.g. Na or K) biodegradable linear alkylbenzenesulfonates, having alkyl groups of about 10 to 16 carbon atoms; parafiin sulfonates, such as the reaction products of alpha olefins and bisulfites (e.g. sodium bisulfite) which are primary paraffin sulfonates of about 10-20, preferably about 15-20, carbon atoms; soaps; sulfates of higher alcohols; salts of a-sulfofatty esters (e.g. of about 10 to 20 carbon atoms, such as methyl a-sulfomyristate or a-sulfotallowate Examples of sulfates of higher alcohols are sodium lauryl sulfate, sodium tallow alcohol sulfate, Turkey red oil or other sulfated oils, or sulfates of monoor diglycerides of fatty acids (e.g. stearic monoglyceride monosulfate), alkyl poly(ethonoxy) ether sulfates such as the sulfates of the condensation products of ethylene oxide and lauryl alcohol (usually having 1 to 5 ethonoxy groups per molecule); lauryl or other higher alkyl glyceryl ether sulfonates; poly(ethenoxy) ether sulfates such as the sulfates of the condensation products of ethylene oxide and nonyl phenol (usually having 1 to 6 oxyethylene groups per molecule).

Examples of soaps are those of fatty acids such as lauric, myristic, stearic, oleic, elaidic, isostearic, palmitic, undecylenic, tridecylenic, pentadecylenic or other saturated or unsaturated fatty acid of 11 to 18 carbon atoms. Soaps of diearboxylic acids may also be used such as the soaps of dimerized linoleic acid. Soaps of such other higher molecular weight acids such as rosin or tall oil acids e.g. abietic acid, may also be employed. Other suitable anionic surface active agents are the carboxylcontaining amides of fatty acids with amino acids (e.g. the lauric acid amide of such amino acids as sarcosine, beta amino propionic acid, polypeptides from hydrolysis of proteins, isethionic acid or N-methyl tauric acid) and soluble salts of such carboxyl-containing amides.

The hydrocarbon radicals of any added anionic detergent materials preferably contain at least about 10 carbon atoms, long chain hydrophobic aliphatic radicals of about 11-18 carbon atoms being particularly suitable, and the cations of the added anionic detergents are advantageously such as to impart water-solubility to the acidic portion of the molecule or to maintain its Watersolubility, e.g. sodium, potassium, triethanolammonium, diethanolammonium, or other alkanolammonium, magnesium (when the surface active agent forms a watersoluble magnesium salt), or ammonium.

The added detergent may be a nonionic or amphoteric detergent. Among the nonionic detergents are the lower alkylene oxide condensation products of hydrophobic compounds which are preferably of 10 to 30 carbons, e.g. ethylene oxide condensates with higher fatty acids, higher fatty acid amides, higher fatty alcohols or alkyl aryl hydrocarbons, having at least and usually from about 5 to 30 oxyethylene groups per molecule. The corresponding higher alkyl mercaptans of thioalcohols, or polyoxypropylene glycols of at least 900 molecular weight condensed with a sufficient number of ethylene oxide groups as known in the art may be used also. Other non-ionics are the alkylolamine condensates of higher fatty acids and ethylene oxide condensates thereof, such as lauric and myristic diethanolamide, coconut fatty acid diethanolarnide, and the like. Among the amphoteric detergents, usually having an alkyl group of -18 carbons, are fatty or higher alkyl imidazolines, such as 1-coco-5-hydroxyethyl-5 carboxymethyl imidazoline known as Miranol CM; and the N-higher alkyl betaalanines such as dodecyl beta-alanine or N-dodecyl iminodipropionic acid (e.g. the materials known as Deriphats), the carboxylic group of the amphoteric detergent may be in the acid form or in the form of the water-soluble salt (e.g. Na salt). Further examples are the disodium salt of l-lauryl-cycloimidium-2-ethoxy-ethionic acid-Z-ethionic acid and its corresponding 2-lauryl sulfate derivative It is preferred that the proportion of added detergent be at most about twice the amount of the olefin sulfonate, eg about 5 to 125% of the weight of the olefin sulfonate, but it is within the broader scope of the invention to employ larger amounts.

A further aspect of the present invention includes the formation of an aqueous slurry having a total solids content of about 30 to 80% by weight, preferably 40 to 75%, in which the sulfonated olefin and any other desired detergent material are in solution or dispersion admixed with a major proportion of water-soluble builder salts, such as having a ratio in the range of about 1:1 to 1:20, preferably 2:5 to 1:10 of organic detergent to inorganic builder salts. The mixture is agitated in any suitable mixing vessel at an elevated temperature as described to form a substantially homogeneous mixture which is flowable (including pumpable). A particularly desirable feature which facilitates processing is the defoaming power or substantial inhibition or elimination of undesirable foam during the mixing operation due to the presence of the sulfonated olefin therein. The mixture can be sent into a drop tank if desired from which it may be .pumped to the heat treatment zone for simultaneous solidification, modification and/or purification of the original sulfonated olefin content in the desired manner. The fluid composition is preferably atomized or forced through spray nozzles into towers wherein the small liquid particles are modified, solidified and dried as they contact the stream or vortex of heated air or products of combustion, maintained as substantially atmospheric pressure (e.g. under a slight vacuum), say a vacuum of /z-2 inches of water. The composition is produced thereby in the form of hollow, thin-walled spheres or beads having a low apparent density (e.g. 0.2-0.7 gram per cc.) and characterized by excellent solubility, uniformity of particles which are essentially non-tacky and non-bleeding in a cardboard container having a lowered free oil or color content as desired.

Particularly desirable results are achieved wherein the sulfonated olefin is treated with a bleaching agent prior to the heat treatment.

The builder salt may be of a type well known in the detergent art generally and may be any suitable alkali metal, alkaline earth metal, or heavy metal salt or combinations thereof. Ammonium or an ethanolammonium salt in a suitable amount may be added also, but generally, the sodium and potassium salts or similar salts are preferred. Examples are the water-soluble sodium and potassium phosphates, silicates, carbonates, bicarbonates, borates, sulfates and chlorides. The builder salts contribute detersive efficiency when used in combination with the salt of the sulfonated olefin. Particularly preferred builder salts are the alkaline builder salts such as polyphosphates, pyrophosphates, silicates, borates, etc. Both Phase I and Phase II sodium tripolyphosphate and mixtures thereof may be successfully used in the compositions. The usual commercial tripolyphosphate consists mainly of the Phase II material. The tripolyphosphate material is usually essentially tripolyphosphate, e.g. 87-95%, with small amounts, e.g. 4-13%, of other phosphates, e.g. pyrophosphate and orthophosphate. Sodium tripholyphosphate in its hydrated form may be used also. Other phosphate salts are tetrasodium pyrophosphate, sodium hexametaphosphate, sodium trimetaphosphate, and the like, including mixtures thereof. Suitable silicates are sodium silicates having an Na O to SiO ratio of 1:2.35, 1:25, 1:32, and so forth. Other suitable materials are borax and sodium carbonate. The proportion of builder salt is preferably, for example, in the range of about 1 to 20 parts per part of the anionically active sulfonate. Alternatively, these salts may be added after the heat treatment, or the neutralization may be effected in the presence of the builder salts which may be blended, in dissolved or finely divided solid condition, With the aqueous caustic neutralizing solution.

A further embodiment relates to such heat-treated particles having an anionic detergent content of about 5- 15 preferably 23-12%, with at least about 5% of said sulfonated olefins and the balance of solids being primarily the water-soluble inorganic salts including sodium sulfate, preferably at least about 10 to 65% alkaline polyphosphate salts. Such anionic detergent content desirably includes the sulfonated olefin in admixture with biodegradable higher alkyl benzene sulfonates, preferably in a ratio sufiicient to exhibit optimum detergent efficiency such as within the range of about 1 to 2 parts of sulfonated olefin per part of the alkyl benzene sulfonate.

Various other materials may be added to the aqueous mixture prior to the heat treatment or thereafter in suitable amounts. Materials such as the higher fatty acid amides may be added to improve detergency and modify the foaming properties in a desirable manner. Examples thereof are the higher fatty acid alkanolamides, preferably having 2-3 carbons in each alkanol group and a fatty acyl radical within the range of 10-18 carbons, preferably 10-14 carbons, such as lauric or myristic monoethanolamides, diethanolamides and isopropanolamides. Tertiary higher alkyl amine oxides such as having about 10-18 carbons in one alkyl group, e.g. lauryl or myristyl dimethylamine oxide, may be added also. Fatty alcohols of 10-18 carbons such as lauryl or coconut fatty alcohols, or cetyl alcohol are suitable additives also. A hydrotropic material such as the lower alkyl aryl sulfonates, e.g. sodium toluene or xylene sulfonates, can assist proceesing also. In general, these materials are added in minor amounts, usually from about /2 to 10%, preferably 1 to 6% based on the total solids.

The mixtures may also contain optical brightening agents or fluorescent dyes (e.g. in amounts in the range of about to /;1%); germicidal ingredients such as halogenated carbanilides, e.g. trichlorocarbanilide, halogenated salicylanilide, e.g. tribromosalicylanilide, halogenated bis-phenols, e.g. hexachlorophene; halogenated trifluoromethyldiphenyl urea; zinc salt of l-hydroxy-Z- pyridinethione and the like (eg in amounts in the range of about M to 2%); soil-suspending agents such as sodium carboxymethyl cellulose or polyvinyl alcohol, preferably both, or other soluble polymeric materials, such as methyl cellulose (the amount of suspending agent being, for example, in the range of about to 2%); antioxidants such as 2,6-di-tert-butylphenol, or other phenolic antioxidant materials (eg in amounts in the range of about 0.001 to 0.1%), coloring agents, bleaching agents and other additives.

Although the present invention has been described with reference to particular embodiments and examples, it will be apparent to those skilled in the art that variations and modifications of this invention can be made and that equivalents can be substituted therefor without departing from the principles and true spirit of the invention.

We claim:

1. In the process for the production of detergents by reacting higher alpha-olefins with dil-uted S to produce a mixture containing higher sultone, ring-opening said sultone, and neutralizing with a base in aqueous medium to produce an aqueous reaction product containing and anionically active neutralized higher olefin sulfonic acid detergent and higher alkanes and olefins insoluble in aqueous and soluble in pentane, the improvement which comprises heat treating said reaction product by contact with a heat transfer material having a temperature of at least 260 F., to raise the temperature of said reaction product to at least about 230 F., said heat treatment being effected at substantially atmospheric pressure while driving off water vapor from said reaction product so that the water content of the product after said heat treatment is in the range of about 112%, said heat treatment being effective to decrease the content of said higher alkanes and olefins, said heat transfer material being a heated gas or a heated solid metallic surface, said reaction product in contact with said heat transfer material being in attenuated form.

2. In the process for the production of detergents 'by reacting higher alpha-olefins with diluted sulfur trioxide to produce a mixture containing higher sultones, ringopening said sultones, and neutralizing with a base in aqueous medium to produce an aqueous reaction product containing an anionically active neutralized higher olefin sulfonic acid detergent and higher alkanes and higher olefins insoluble in aqueous ethanol and soluble in pentane, the improvement which comprises heat treating said reaction product by atomizing said reaction products into hot air at a temperautre of at least 260 F. to raise the temperature of said reaction product to at least 230 F., said heat treatment being effected at substantially atmospheric pressure while driving ofl? water vapor from -12 said reaction product so that the water content of the product after said heat treatment is in the range of about 1l2%, said heat treatment being effective to decrease the content of said higher alkanes and olefins.

3. Process as set forth in claim 1 in which said mixture containing a higher sultone is treated with sulfuric acid under substantially non-hydrolyzing conditions before neutralizing.

4. Process as set forth in claim 1 in which the aqueous reaction product contains also neutralized higher hydroxyalkanesulfonic acid and higher sultone, said sultone being anionically inactive.

5. Process as set forth in claim 2 in which said aqueous reaction product is mixed with an inorganic builder salt prior to said heat treatment.

6. Process as set forth in claim 2 in which said salt comprises sodium tripolyphosphate, the ratio of said builder salt to anionically active sulfonated olefin being in the range of about 1:1 to 10:1, the water content of the mixture just before said atomization being at least about 20%.

7. Process as set forth in claim 2 in which the ratio of said pentane-soluble higher alkanes and olefins to the anionically active material in the reaction product prior to said heat treatment is in range of about 1:4 to 1:100.

8. Process as set forth in claim 2 in which the duration of said heat treatment is up to about 10 minutes.

9. Process as set forth in claim 8 in which said duration is about 10 seconds to a minute.

10. Product produced by the process of claim 1.

11. Process as set forth in claim 2 in which said olefin sulfonate has 12 to 21 carbon atoms.

12. Process as in claim 2 in which the aqueous reaction product is mixed, prior to said heat treatment, with sodium linear alkylbenzenesulfonate detergent having 10 to 16 carbon atoms in the alkyl group, the proportion of said alkylbenzenesulfonate being about 5 to of the weight of the olefin sulfonate, and said hot air is at a temperature of 300700 F.

References Cited UNITED STATES PATENTS 2,192,713 9/1937 Mottern 2605l3 2,613,218 6/1950 Stoneman 260504 2,691,040 10/1954 Bloch et al. 2605l3 MAYER WEINBLA'IT, Primary Examiner P. E. WILLIS, Assistant Examiner US. Cl. X.R. 

